We stayed at the Residence Inn on Vermont Street (note that DC has two Residence Inns; I know nothing about the other one). We won it on Priceline for $50/night and were VERY SATISFIED for that price. If we'd paid $150, I wouldn't have considered it such a good value.
Good points:
Most importantly, we did feel safe in this hotel. The park just by the Metro station was FULL of homeless people in the early AM and late evenings, which was a little disconcerting. Some of them asked us for money, but no one did anything to make us feel unsafe.
It was located roughly five blocks from the White House and seven blocks from the Smithsonian museums.
The closest Metro station -- McPherson station? -- was a block and a half away.
We had the smallest studio room, and it had a queen sized bed and an L-shaped sofa with a single pull-out sofa (I'd never seen such a thing before). We just asked for extra sheets and made up the other end of the sofa for our youngest child -- if she hadn't been small, this wouldn't have worked; however, if she'd been a little bigger, we could've asked for a roll-away. The room had plenty of space for one.
The room also had a small kitchen, which was very welcome.
Like most DC hotels, all the rooms are on upper levels, while the lower levels have stores or restaurants. Our hotel was situated above a CVS, which -- in addition to the usual drugstore items -- sold a small quantity of groceries, which was ideal for us. You can get into the CVS without even going out on the street.
Like all Residence Inns, this one offered a free (well, included in the price) breakfast. Since food in DC was quite expensive, we thought this was a great thing, especially since we'd only paid $50/night to stay there!
Parking was something like $20/night, though this is typical for DC. I was glad we didn't have a car.
The service we received was top-notch. Our flight was early in the day, and we came to the hotel well ahead of our check-in time, thinking we'd aske them to store our luggage while we started sight-seeing -- nope, they had a room ready for us and invited us to go have some breakfast! Throughout our stay, the staff simply couldn't have treated us any better.
Bad points:
This hotel is not new, and it lacks "swanky-ness". Though it's clean and convenient, a few parts could use a coat of paint, etc.
The hotel does not have a pool or a work-out room; however, patrons are allowed to use the facilities at the Marriott a few blocks away.
This is probably an unusual situation, but the hotel is surrounded by sandwich shops and delis! NO nice restaurants. You can take the Metro to plenty of nice places, but you can't really walk to much of anything.